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Journal of Sustainable Mining

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© Central Mining Institute 2014

Durga Charan Panigrahi and Devi Prasad Mishra (2014). CFD simulations for

the selection of an appropriate blade profile for improving energy efficiency

in axial flow mine ventilation fans. Journal of Sustainable Mining, 13(1), 15–21.

doi: 10.7424/jsm140104

ORIGINAL PAPER

Received: 8 April 2014 Revised: 28 April 2014 Published online: 20 May 2014

CFD SIMULATIONS FOR THE SELECTION OF AN APPROPRIATE BLADE PROFILE FOR

IMPROVING ENERGY EFFICIENCY IN AXIAL FLOW MINE VENTILATION FANS

Durga Charan Panigrahi1 and Devi Prasad Mishra

2

1 Indian School of Mines (Dhanbad, Jharkhand, India) 2 Department of Mining Engineering, Indian School of Mines (Dhanbad, Jharkhand, India)

Corresponding author: e-mail: [email protected], tel.: +91 9430191673; fax: +91 326 2296628/2296563

ABSTRACT

Purpose

This study focuses on one of the key design aspects of mine ventilation fans, i.e. the selection of an appropriate aerofoil

blade profile for the fan blades in order to enhance the energy efficiency of axial flow mine ventilation fans, using CFD

simulations.

Methods

Computational simulations were performed on six selected typical aerofoil sections using CFD code ANSYS Fluent 6.3.26

at angles of attack varying from 0 to 21 at an interval of 3 and at Reynolds number Re = 3 × 106, and various aerody-

namic parameters, viz. coefficients of lift (Cl) and drag (Cd) as a function of angle of attack (α) were determined to assess

the efficiency of the aerofoils.

Results

The study revealed that the angle of attack has a significant effect on the lift and drag coefficients and stall condition oc-

curred at α values of 12 and 15 in most of the aerofoils. Based on the criterion of higher lift to drag ratio (Cl/Cd), a blade

profile was chosen as the most efficient one for mine ventilation fans.

Practical

implications

This study forms a basis for selecting appropriate blade profiles for the axial flow fans used for ventilation in mining

industry.

Originality/

value

The application of an appropriate aerofoil blade profile will impart energy efficiency to the mine ventilation fans and

thereby result in energy saving in mine ventilation.

Keywords

mine ventilation, axial flow fan, energy efficiency, aerofoil, lift and drag, CFD

1. INTRODUCTION

Mine ventilation fans run 24 hours a day and throughout

the year for maintaining a comfortable working environment

for the miners working below ground. Mostly, conventional

aluminium alloy bladed fans are used for underground mine

ventilation, which are neither properly designed nor appro-

priately selected to suit the desired condition. As a result, the

consumption of electricity during their operation constitutes

the largest component of the operating cost for mine ventila-

tion and accounts for one third of a typical underground

mine's entire electrical power cost (Vergne, 2003). Belle

(2008) has reported that the consumption of electricity by the

main ventilation fan of a major mining company alone can be

in the region of 120 MW. Therefore, ventilation is undoubt-

edly the most significant cost component of any underground

mine and a major part of this is made up by the main mine

fans. The electric power consumption profile in Polish mines,

reported by Krzystanek and Wasilewski (1995), revealed that

the mine fans together with dewatering pumps and compres-

sors that operate continuously consume over 40% of the total

electrical energy consumption of the mines and out of which

14% is consumed by the main fans itself.

In this energy crunch world, the mining industry is facing

the challenges of increasing energy costs. Therefore, investi-

gations are ongoing and more focus is being given to reduc-

ing energy consumption in the ventilation systems. Enhanc-

ing energy efficiency is one of the alternatives for minimizing

energy consumption in any system. In mine ventilation, ener-

gy consumption can be reduced by improving efficiency with

the suitable design of ventilation fans. The design and selec-

tion of the ventilation fans are of foremost importance with

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Journal of Sustainable Mining (2014) 13(1), 15–21

16

regards to operation and energy consumption. Furthermore,

improvement in overall ventilation system efficiency can be

achieved by reducing wasteful air power and enhancing fan

efficiency. It is obvious that the power consumption will be

less if the fan efficiency is more and vice versa (Sharma,

2002). The power consumption in fans depends to a large

extent on the various losses involved, viz. impeller friction

loss, entry loss, shock loss, clearance loss and diffuser loss,

and the high losses in fans which are attributed to poor de-

signs (Eck, 1973). Sen (1997) observed that the excess power

consumption in axial flow main mine ventilation fan occurs

because of the unrefined design approach, careless selection

and incorrect installation of the fan. According to Sen (1997),

a combination of aerodynamic, mechanical, electrical, struc-

tural and operational factors are involved in any overall opti-

mization exercise, i.e. attainment of high fan efficiency or

minimum power consumption. According to Hustrulid and

Bullock (2001), the main reasons for very poor efficiency of

old design colliery fans are due to poor aerodynamic design,

improper fan selection and poor aerodynamics at the fan site,

which are the root causes that yield static efficiencies below

50%. Therefore, enhancing energy efficiency in mine fans by

minimizing various losses is an important facet of energy

saving and it is mainly governed by proper design of the

ventilation fans. The design of fan blades constitutes the most

significant feature of the fans. Belle (2008) has reported that

a 10% increase in main fan efficiency with a 10% reduction

in electricity consumption may result in a saving of 10.81 MW

of electricity per annum; this would have a net present benefit

of US$ 16.08 million over 10 years. Several other approach-

es, viz. use of fan blades made of composite material such as

FRP (fibreglass reinforced plastic), application of variable

speed drives and the ventilation-on-demand (VOD) concept

have also been tried in order to reduce energy consumption in

ventilation fans (Mishra, 2004; Panigrahi, Mishra, Divaker,

& Sibal, 2009).

The shape of the blades, which are of aerofoil sections in

the case of axial flow fans, plays an important role in the

performance of the fans and fan efficiency is greatly depend-

ent on the profile of the blades. Therefore, there is a scope for

improving energy efficiency by reducing losses and enhan-

cing the efficiency of fans by using aerodynamically de-

signed fan blades made of suitable material. From this point

of view, the design of mine fan blade profiles with suitable

aerofoil section is very much desired. Nowadays, computa-

tional fluid dynamics (CFD) is widely used in the field of

aerodynamics for design and analysis of aerospace vehicles.

Simulation of airflow around the aerofoil sections using CFD

has been studied by several researchers (Kieffer, Moujaes &

Armbya, 2006; Eleni, Athanasios, & Dionissios, 2012; Raja-

kumar & Ravindran, 2012; Bai, Sun, Lin, Kennedy, & Wil-

liams, 2012). Rumsey and Ying (2002) reported CFD capa-

bility in predicting surface pressures, skin friction, lift, and

drag with reasonably good accuracy at angles of attack below

stall in high-lift flow fields.

Keeping this in mind and with a broader aim of reducing

energy consumption in mine ventilation fans, numerical si-

mulations of the aerodynamic effects of different angles of

attack on the selected aerofoil sections have been carried out

in this study in a turbulent Reynolds number flow using the

k-ε turbulence model. The aerodynamic characteristics of the

aerofoil sections viz. lift and drag coefficients at various

angles of attack are determined for selecting a suitable profile

for the axial flow mine ventilation fan blades giving the high-

est lift to drag ratio.

2. GENERAL AERODYNAMICS OF AXIAL FLOW

FANS

A fan is simply a machine which develops the pressure

necessary to produce the required airflow rate and overcome

flow resistance of the system by means of a rotating impeller

using centrifugal or propeller action, or both. The axial flow

fans are commonly used in mine ventilation in lieu of centri-

fugal fans due to high efficiency, compactness, non-overlo-

ading characteristics, development of adequate pressure, etc.

(Misra, 2002). The axial flow fan in its simplest form as

diagrammatically shown in Figure 1 incorporates a rotor,

which consists of a hub fitted with aerofoil section blades in

a radial direction. The blades or vanes which constitute the

main component of axial flow fan are the surfaces that work

by means of dynamic reaction on the air and develop positive

air pressure during their rotation due to the development of

lift force. The forces acting on a typical aerofoil section of an

axial flow fan blade are shown in Figure 2. The lifting force

acts at right angles to the air stream and the dragging force

acts in the same direction of the air stream and is responsible

for losses due to skin friction.

Fig. 1. The schematic of axial flow fan (Vutukuri & Lama, 1986)

Fig. 2. Forces acting on a typical aerofoil section of axial flow fan blade

The efficiency of axial flow fans is greatly dependent on

the profile of the blade, and the aerodynamic characteristics

of the fan blades are strongly affected by the shape of the

blade cross section. The cross section of fan blades is of

Journal of Sustainable Mining (2014) 13(1), 15–21 17

a streamlined asymmetrical shape, called the blade’s aerody-

namic profile and is decisive when it comes to blade perfor-

mance. Even minor alterations in the shape of the profile can

greatly alter the power curve and noise level. Therefore, it is

essential to choose an appropriate shape with great care, in

order to obtain maximum aerodynamic efficiency. An aero-

dynamic profile with optimum twist, taper and higher lift-

drag ratio can provide total efficiency as high as 85–92%.

The axial flow fan blades are of aerofoil sections and the idea

behind using aerofoil blades is to maintain the proper stream-

lining of air to reduce losses caused due to form drag as well

as from strength considerations (Misra, 2002). The blade

performance characteristics may be predicted from the aero-

dynamic characteristics such as lift and drag coefficients of

the chosen aerofoil section and given by the following equa-

tions:

Cl =

AV2

1

L

2

(1)

Cd =

AV2

1

D

2

(2)

where Cl is the coefficient of lift, Cd is the coefficient of drag,

L is the lift force, D is the drag force, ρ is the density of air, V

is the velocity of undisturbed airflow and A is the blade refe-

rence area.

The aerodynamic lifting force is a vital component and

must be much greater than the drag component. Since lift

contributes to the head generated by the fan and the drag

causes loss due to skin friction in the wake behind the vane,

the profile offering higher L/D ratio is considered more effi-

cient (Misra, 2002). Maximum lift to drag provides a combi-

natory measure of the performance of the aerofoil and, there-

fore, the Cl/Cd curve can be likened to the efficiency charac-

teristic of a fan. In the case of mine ventilation fans, an

aerofoil profile generating high lift coefficient and offering

high lift to drag ratio is needed for minimizing losses, pro-

ducing high head and improving the efficiency of the fan

provided it fulfils the other constraints like economy, change

in mine resistance over time and other factors. These re-

quirements are better fulfilled by the non-symmetrical aero-

foils and are, therefore, commonly preferred for fan blades

than symmetrical ones.

The lift and profile drag of the aerofoil shaped blades,

when move through air, vary with the structure of the aerofoil

and variations in the angle of attack (α). The angle of attack

is the angle between the velocity vector and the chord line of

the aerofoil (Figure 2). As the angle of attack increases, the

coefficient of lift increases in a near-linear manner. However,

at an angle of attack usually between 12 and 18°, breakaway

of the boundary layer occurs on the upper surface. This caus-

es a sudden loss of lift and an increase in drag, known as stall

condition. In this condition, the formation and propagation of

turbulent vortices causes the fan to vibrate excessively and to

produce additional low frequency noise (McPherson, 1983).

The aerodynamic design of axial flow fans is a very com-

plex process and mainly consists of designing two-

dimensional blade sections at various radii. Over the past few

decades, lots of effort has been put in to aerodynamic im-

provements of mine fans. Advances in aerodynamic design,

which incorporate aerofoil section blading with lower aspect

ratios, higher solidities and higher stagger angles have led to

an increase in static-pressure rise. In addition to aerodynamic

improvements, the use of improved materials and advanced

mechanical design techniques also had a significant contribu-

tion. In conventional aluminium alloy bladed mine fans, their

cross section barely matches a suitable aerofoil geometry that

can develop sufficient lift and minimal drag forces. Moreo-

ver, the roughness of the blade surface considerably increases

the losses. As a result, they may not reach the desired effi-

ciency and cause a loss of energy. Eckert (1953) found that

unmachined cast-iron blades give an efficiency ~10% lower

than machined blades. Hence, careful smoothening of the

blade surfaces is essential to obtain better fan efficiency.

3. CFD ANALYSIS OF THE AEROFOIL SECTIONS

In this study, the CFD package ANSYS Fluent 6.3.26 is

used to perform the numerical simulation of airflow around

the selected aerofoil sections. Fluent solvers are based on the

finite volume method in which the domain is discretized into

a finite set of control volumes (or cells). It solves conserva-

tion equations for mass and momentum to determine the

pressure distribution and therefore fluid dynamic forces act-

ing on the wing as a function of time. Six aerofoil sections,

viz. EPPLER 420, EPPLER 544, EPPLER 855, FX 74 CL5

140, NACA 747A315 and NACA 64(3)-418 have been

chosen based on an extensive literature review for 2-D

simulation to select a suitable aifoil section for the blades of

axial flow mine ventilation fans. Most of these aerofoils are

used in aeroplanes, wind turbines, high velocity rotors, sail-

planes and rotorcrafts etc.

3.1. Geometry creation and meshing

The aerofoil geometries of the chosen aerofoils have been

created with the coordinates obtained from the airfoil coordi-

nates database (http://www.ae.illinois.edu/m-selig/ads/coord_

database.html) and shown in Figures 3.

Gambit 2.4.6, the pre-processor of Fluent 6.3.26 is used to

create the discretized domain or mesh with a far-field and

near-field area and exported to Fluent for analysis. Computa-

tional domain or the far-field distance, which is about 15

times the size of that of the chord length surrounding the

centrally located aerofoil, is created for each profile. The

domain boundary is set as a pressure-far-field and the surface

of the aerofoil is set as wall. The meshing is done based on

two-dimensional structured C-grid topology in x-y direction

giving rise to average quadrilateral cells of about 160000 for

all of the aerofoils. Figure 4 shows the meshed flow domain

surrounding an aerofoil. The resolution of the mesh close to

the aerofoil region is made greater for better computational

accuracy. The height of the first cell adjacent to the surface of

the aerofoils is set to 10–5

, corresponding to a maximum y+ of

approximately 0.2.


18

a)

-0.05

0

0.05

0.1

0.15

0.2

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1

EPPLER 420 Airfoil

b)

-0.1

-0.05

0

0.05

0.1

0.15

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1

EPPLER 544 Airfoil

c)

-0.1

-0.05

0

0.05

0.1

0.15

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1

EPPLER 855 Airfoil

d)

-0.05

0

0.05

0.1

0.15

0.2

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1

FX74 CL5 140 Airfoil

e)

-0.1

-0.05

0

0.05

0.1

0.15

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1

NACA 747A315 Airfoil

f)

-0.1

-0.05

0

0.05

0.1

0.15

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1

NACA 64(3)-418 Airfoil

Fig. 3. The aerofoil geometries: a – EPPLER 420, b – EPPLER 544, c – EPPLER 855, d – FX 74 CL5 140, e – NACA 747A315

and f – NACA 64(3)-418

Fig. 4. The meshed flow domain surrounding aerofoil FX 74 CL5 140

3.2. CFD analysis for determination of lift and drag

coefficients

The aerofoils with meshed flow domain are solved with

Fluent solver for determining the lift and drag coefficients

giving various input parameters, such as airflow direction, flow

velocity (15 m/s), air density (1.225 kg/m3), angle of attack,

boundary conditions etc. The free air stream temperature is

considered as 300 K, which is same as the environment tem-

perature and at this given temperature, the density and viscosi-

ty of the air is ρ = 1.225 kg/m3

and μ = 1.7894 × 10–5

kg/ms

respectively. The flow is assumed to be incompressible. At

this stage it is important to mention that the accuracy of

CFD-based lift and drag prediction depends on the geometry

representation, mesh size, flow solver, convergence level,

transition prediction and turbulence model (Oskam & Sloo,

1998). For the numerical modelling of fluid-structure interac-

tion problems, the choice of turbulence model is important.

In this study the most widely used k-ε turbulence model is

chosen for simulation due to its simplicity (Kieffer et al.,

2006; Hoo, Do, & Pan, 2005). This model, proposed by

Launder and Spalding (1974), includes standard renormaliza-

tion-group (RNG) and realizable models. The Reynolds number

for the simulations is considered as Re = 3 × 106. The angles of

attack (AoA) are varied from 0 to 21 at 3 intervals for all

the aerofoils. Additionally, the coefficients of lift (Cl) and

drag (Cd) are determined at different angles of attack. There-

after, the graphs of lift and drag coefficients versus angle of

attack are plotted and the AoA corresponding to the maxi-

mum lift to drag ratio is determined. The pressure and veloci-

ty contours surrounding the aerofoil sections are also gener-

ated at the angle of attack which produces maximum lift to

drag ratio for analysing the variation in air velocity and pres-

sure around the aerofoil.

4. RESULTS AND DISCUSSION

The static pressure and velocity plots showing the magni-

tude of the static pressure and air velocity in the flow field are

obtained from the CFD simulation. The velocity and pressure

distributions for all the aerofoils follow a similar pattern for

all angles of attack. For instance, the contours of static pres-

sure and velocity vector which are coloured according to

velocity magnitude across the aerofoil EPPLER 420 at

a particular angle of attack (AoA) are presented in Figures 5

through 8.

Fig. 5. Contours of static pressure across aerofoil EPPLER 420


Fig. 6. Velocity vectors coloured by velocity magnitude across aerofoil EPPLER 420

Fig. 7. Velocity vectors coloured by velocity magnitude at the leading edge of aerofoil EPPLER 420

Fig. 8. Velocity vectors coloured by velocity magnitude at the trailing edge of aerofoil EPPLER 420

As expected from the normal aerofoils, the static pressure

contours show that the pressure is negative on the upper sur-

face and positive on the lower surface of the aerofoil, which

is marked by a higher air velocity on the upper surface and

lower velocity on the lower surface. The higher static pres-

sure at the lower surface of the aerofoil effectively pushes the

aerofoil upwards and is responsible for the generation of lift

force, which acts perpendicularly to the inflowing airstream.

The variation in velocity, which is caused due to the curva-

ture of the aerofoil sections, can be clearly observed from the

contours of velocity vectors which is coloured according to

velocity magnitude. This phenomenon complies with Ber-

noulli’s equation. The air accelerates on the upper surface, as

marked by an increase in the velocity magnitude and intensity

of the colours of the velocity vectors. The reverse case is

observed on the trailing edge of the aerofoil, i.e. the flow on

the upper surface decelerates and converges with the flow on

the lower surface. On the leading edge of the aerofoil (Figure

7), a stagnation point can be seen where the velocity of flow

is nearly zero.

The variation of aerodynamic coefficients, i.e. the coeffi-

cients of lift (Cl) and drag (Cd) with angles of attack for all

the aerofoil sections obtained from the CFD analysis are

shown in Figure 9. The figure clearly shows that the lift and

drag coefficients increase steadily with angles of attack. The

coefficient of lift attains its maximum value at 12° AoA for

airfoils EPPLER 855, FX 74 CL5 140 and NACA 64(3)-418,

while it reachers its maximum of 15° for airfoils EPPLER

420, EPPLER 544 and NACA 747A315. Beyond these an-

gles, the coefficient of lift decreases and the coefficient of

drag decreases or remains relatively constant. At these AoAs,

flow separation at the upper surface of the aerofoil sections

can be observed. This indicates that the aerofoils begin to

approach the “stall condition”.

a)

0

0.5

1

1.5

2

2.5

3

0 3 6 9 12 15 18 21 24

Ae

rod

ynam

ic C

oe

ffic

ien

ts (C

lan

d C

d)

Angle of Attack, Degrees

Aerofoil EPPLER 420

Coefficient of Lift (Cl) Coefficient of Drag (Cd)

b)

0

0.5

1

1.5

2

2.5

0 3 6 9 12 15 18 21 24

Ae

rod

ynam

ic C

oe

ffic

ien

ts (C

lan

d C

d)


Aerofoil EPPLER 544


c)

0

0.5

1

1.5

2

2.5

0 3 6 9 12 15 18 21 24

Ae

rod

ynam

ic C

oe

ffic

ien

ts (C

lan

d C

d)


Aerofoil EPPLER 855



20

d)

0

0.5

1

1.5

2

2.5

3

0 3 6 9 12 15 18 21 24

Ae

rod

ynam

ic C

oe

ffic

ien

ts (C

lan

d C

d)


Aerofoil FX 74 CL5 140


e)

0

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

1.8

2

0 3 6 9 12 15 18 21 24

Ae

rod

ynam

ic C

oe

ffic

ien

ts (C

lan

d C

d)


Aerofoil NACA 747A315


f)

0

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

0 3 6 9 12 15 18 21 24

Ae

rod

ynam

ic C

oe

ffic

ien

ts (C

lan

d C

d)


Aerofoil NACA 64(3)-418


Fig. 9. Aerodynamic coefficients vs. angle of attack for the aerofoils a – EPPLER 420, b – EPPLER 544, c – EPPLER 855, d – FX 74 CL5 140,

e – NACA 747A315 and f – NACA 64(3)-418

Table 1 summarizes the maximum Cl offered by the aero-

foil sections and their corresponding angle of attack values.

In addition, the Cd corresponding to the maximum Cl and the

Cl/Cd ratios, a measure used for prediction of efficiency of

the aerofoil sections are presented in the table. The results

indicate that the maximum Cl, which varies in the range of

1.425–2.667 is obtained at AoAs ranging from 12 to 15 de-

grees in most of the aerofoil sections. Thereafter, the Cl falls

and the region of high velocity begins to separate from the

aerofoil surface at the trailing edge, giving rise to the “stall

condition”. Aerofoil FX-74 L5 40 offers its highest Cl of

2.667 at AoA of 12°. It can also be noticed that, comparative-

ly, NACA aerofoils offer a higher lift to drag ratio than the

EPPLER aerofoils. Although the aerofoil NACA 747A315

offered a lower Cl value of 1.858, due to the least correspond-

ing drag value of 0.1394, the Cl/Cd ratio, i.e. 13.329 happens

to be the highest amongst all the aerofoils analyzed in this

study. This indicates that the aerofoil NACA 747A315 offers

the least resistance to the airflow and can provide better effi-

ciency to the fans. Therefore, the NACA 747A315 aerofoil

section is the final choice for the fan blades.

Table 1. Summarized CFD analysis results of the aerofoil sections

Profile ID Angle of Attack

(Degrees) Max. Cl

Corresponding Cd

Cl/Cd ratio

E-420 15 2.553 0.551 4.633

E-544 15 2.228 0.563 3.957 E-855 12 1.934 0.408 4.740

FX-74 L5 40 12 2.667 0.549 4.858

NACA 747A315 15 1.858 0.139 13.367 NACA 64(3)418 12 1.425 0.281 5.071

5. CONCLUSIONS

Minimizing various losses involved in fan system can im-

prove efficiency, which in turn facilitate savings in energy

consumption. Fan efficiency is greatly dependent on the

profile of the blade. The lift to drag ratio is a measure of the

aerodynamic efficiency of the fan blade and an aerofoil with

higher lift to drag ratio is considered as the most efficient

one. This study presents CFD simulations of drag and lift

coefficients of six different airfoils using the ANSYS Fluent

software, which is a finite volume based commercial code, to

help with the selection of an energy-efficient blade profile for

mine ventilation fans. In this study, six different airfoil sec-

tions are considered for CFD simulations to study the effect

of the variation of angle of attack on the aerodynamic coeffi-

cients. The results indicate that NACA aerofoils offer a high-

er lift to drag ratio and the aerofoil NACA 747A315 offers

the highest Cl/Cd ratio of all at 13.329. Therefore, if the

blades of axial-flow mine ventilation fans are made of NACA

747A315 aerofoil section, it can provide better efficiency to

the fans and help in minimizing energy consumption.

Acknowledgements

This research is sponsored by Petroleum Conservation Re-

search Association (PCRA), New Delhi, India. The authors

wish to express their sincere gratitude and appreciation to

PCRA for funding the project.

References

Bai, Y., Sun, D., Lin, J., Williams, F., & Kennedy, D. (2012). Nu-

merical aerodynamic simulations of a NACA airfoil using CFD

with block-iterative coupling and turbulence modelling. Interna-

tional Journal of Computational Fluid Dynamics, 26(2), 119–132.

Belle, B.K. (2008). Energy savings on mine ventilation fans using

“Quick-Win” Hermit Crab Technology-A perspective. In Jr.

K.G. Wallace (Ed.), 12th U.S./North American Mine Ventilation

Symposium (pp. 427–433). Reno: The University of Nevada.

Eck, B. (1973). Fans; design and operation of centrifugal, axial

flow, and cross-flow fans. Oxford: Pergamon Press.

Eckert, B. (1953). Axial Kompressoren und Radial Kompressoren.

Berlin: Springer Verlag.

Eleni, D.C., Athanasios, T.I., & Dionissios, M.P. (2012). Evaluation

of the turbulence models for the simulation of the flow over

a National Advisory Committee for Aeronautics (NACA) 0012

airfoil. Journal Mechanical Engineering Research, 4(3), 100–111.

Hoo, E., Do, K.D., & Pan, J. (2005). An investigation on the lift

force of a wing pitching in dynamic stall for a comfort control

vessel. Journal of Fluids and Structure, 21, 707–730. Retrived

from http:// www.ae.illinois.edu/m-selig/ads/coord_database.html.

Accessed on 18.05.2011.

Hustrulid, W.A., & Bullock, R.L. (2001). Underground mining

methods: engineering fundamentals and international case studies.

Englewood, CO: Society for Mining, Metallurgy and Exploration.

Kieffer, W., Moujaes, S., & Armbya, N. (2006). CFD study of

section characteristics of Formula Mazda race car wings. Ma-

thematical and Computer Modelling, 43, 1275–1287.


Krzystanek, Z., & Wasilewski, S. (1995). Monitoring and control of

main fans for minimization of power consumption. In A.M. Wa-

la (Ed.), Proceedings of the 7th US Mine Ventilation Symposium

(pp. 75–81). Littleton, CO: Society for Mining, Metallurgy, and

Exploration.

Launder, B.E., & Spalding, D.B. (1974). The numerical computation

of turbulent flows. Computer Methods in Applied Mechanics

and Engineering, 3(2), 269–289.

McPherson, M.J. (1983). Subsurface Ventilation and Environmental

Engineering. Netherlands: Kluwer Academic Publishers.

Mishra, D.P. (2004). A Study of Energy Consumption Profile of

Main Mine Ventilation Fans and Development of a Technique to

Reduce the Energy Requirement in Such Systems. Dissertation.

Dhanbad: Indian School of Mines.

Misra, G.B. (2002). Mine Environment and Ventilation. New Delhi:

Oxford University Press.

Oskam, B., & Sloof, J.W. (1998). Recent advances in computational

aerodynamics at NLR. AIAA Paper 98-0138. doi: 10.2514/6.

1998-138.

Panigrahi, D.C., Mishra, D.P., Divaker, C., & Sibal, S.J. (2009).

Application of fibreglass reinforced plastic blades in main mine

ventilation fans: an innovative concept of energy saving. In D.C.

Panigrahi (Ed.), Mine Ventilation (pp. 709–715). New Delhi:

Oxford & IBH Publishing Co. Pvt. Ltd.

Rajakumar, S., & Ravindran, D. (2012). Iterative approach for opti-

mising coefficient of power, coefficient of lift and drag of wind

turbine rotor. Renewable Energy, 38(1), 83–93.

Rumseya, C.L., & Ying, S.X. (2002). Prediction of high lift: review

of present CFD capability. Progress in Aerospace Sciences,

38(2), 145–180.

Sen, P.K. (1997). Reducing power consumption for axial flow mine

ventilation fans. Journal of Mines, Metals and Fuels, 45(9–10),

301–303. Sharma, R.N. (2002). Economics of mine ventilation. In Procee-

dings of International Conference on Mineral Industry: Issues

on Economics, Environment and Technology (pp. 75–87). India:

The Mining, Geological and Metallurgical Institute of India.

Vergne, J.N.D.L. (2003). The Hard Rock Miner’s Handbook. North

Bay, ON: McIntosh Engineering Limited.

Vutukuri, V.S., & Lama, R.D. (1986). Environmental Engineering

in Mines. Cambridge: Cambridge University Press.

cfd simulations for selection of appropriate blade profile...

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